NATO Secretary General Jens Stoltenberg has announced the stepping up of efforts to provide support to Ukraine by the alliance, after a phone conversation with Ukrainian President Volodymyr Zelensky and.

"I just spoke with President Zelensky," Stoltenberg wrote on Twitter.

"NATO Allies are stepping up support with air-defence missiles, anti-tank weapons, as well as humanitarian and financial aid," he said.

EU high representative for foreign affairs and security policy Josep Borrell earlier declared that the bloc will provide weapons for Ukraine’s armed forces, amid fierce battles throughout the country.